The BTR Canted Valve LS Cylinder Head is a bare aluminum cylinder head built for LS1 engines in the 6-bolt deck configuration. It uses BTR's canted-valve design — intake rotated 5° and exhaust rotated 3° — to unshroud the valves and increase airflow, with over 360 CFM of intake flow at .650" lift reported using BTR's in-house port program. This is a porter's casting: it ships with finished valve guides and unfinished valve seats, ready for a cylinder head porter to complete final port, chamber, and deck work. Valves, springs, and valve spring hardware are not included.
- Part Number: BTR-CVH1P-6U
- Application: GM LS1 engines (cathedral port, 3.780" bore)
- Bolt Pattern: 6-bolt deck
- Material: Aluminum, bare casting
- Intake Style: Canted valve, angle plug — 11° intake (5° canted) / 13° exhaust (3° canted)
- Casting Details: Cast in Iowa; designed, tested, and machined in Kentucky; porter's casting with finished guides / unfinished seats
- Valve Guides: OEM-type powdered metal guides (finished)
- Valve Sizing: Uses OEM LT1 2.125" steel hollow-stem intake and 1.590" steel exhaust valves (LT4 Ti intake / L8T Inconel exhaust valves usable with lash caps)
- Deck Thickness: .750" boost-friendly deck
- Pushrod Length Reference: Clears 3/8" pushrods; typical intake length 7.925"-8.025", exhaust length 7.900"-8.000"
- Compatibility: OEM-style LS1 pedestal rockers, intake/exhaust manifolds, LS-style valve covers, Gen V LT long-reach spark plugs, valve spring kits up to 1.350" O.D.
- Install Notes: Expect to remove .100"+ of additional material from chambers/runners during porting; sealant required on intake rocker bolt threads that intersect the port; the M10x1.5 accessory hole (commonly used for a dipstick) is shallower than OEM to prevent water jacket intrusion — verify dipstick bolt fit before final assembly; C5/C6 Corvette alternator brackets require minor clearancing to bolt flush
FAQ
Is the BTR-CVH1P-6U cylinder head ready to install out of the box?
No. It is a porter's casting that ships with finished valve guides and unfinished valve seats; final port sizing, chamber sizing, deck milling, and valve seat cutting are required before use, and valves/springs/hardware are not included.
What is the bore and valve angle on the BTR-CVH1P-6U?
It is designed for the LS1's cathedral port 3.780" bore, using a canted-valve layout with the intake rotated 5° and exhaust rotated 3° (11° intake / 13° exhaust total angle).
What size valves does this cylinder head use?
It uses OEM LT1-style 2.125" steel hollow-stem intake valves and 1.590" steel exhaust valves; LT4 Ti intake and L8T Inconel exhaust valves can also be used with lash caps.
What pushrod length should I plan for with this cylinder head?
The head clears 3/8" pushrods, with a typical intake pushrod length of 7.925"-8.025" and exhaust length of 7.900"-8.000", though final length should be verified for each build.
Are there any fitment quirks to check before final assembly?
Yes — the M10x1.5 accessory hole commonly used for a dipstick is shallower than OEM to prevent water jacket intrusion, so the dipstick bolt should be checked before final assembly, and C5/C6 Corvette alternator brackets require minor clearancing to bolt up flush to the engine.
